Diminuição do índice de necrose em enxertos cutâneos em coelhos mediante a aplicação de células tronco mesenquimais xenógenas / Reducing of the necrosis index in skin grafts in rabbits through application of xenogenous mesenchymal stem cells

O presente estudo teve como objetivo avaliar a inflamação em auto-enxertos cutâneos obtidos no terceiro, sétimo e décimo quarto dia de pós-operatório, além disso, buscou-se determinar diferenças no processo de cicatrização no grupo tratado com células tronco mesenquimais xenógenas em relação ao grupo controle utilizando a avaliação microscópica e imuno-histoquímico. A avaliação microscópica foi realizada utilizando cortes histológicos corados pela técnica de histoquímica com hematoxilina-eosina (HE), e a imuno-histoquímica, com cortes submetidos a anticorpos específicos. As variáveis analisadas foram quantidade de vasos, células inflamatórias, COX-2, Macrófagos e presença de necrose. Os dados foram analisados estatisticamente pelo software R. A quantidade de vasos foi maior (p<0,0001) no grupo tratamento (GT) durante o dia 3, enquanto no grupo controle (GC) foi maior no dia 7. No dia 3 houve menor porcentagem de necrose no grupo tratamento (GT) (p = 0,038). Nos demais dias avaliados não houve diferença entre a porcentagem de necrose observada nos dois tratamentos (p = 0,98), sendo de 53% para o grupo controle (GC) e 47% para o grupo tratamento (GT). Em relação ao número de macrófagos não houve diferença entre os grupos (p = 0,5637). Entretanto, entre os dias houve diferença significativa (p = 0,0223), sendo menor número de macrófagos no terceiro dia. A imunomarcação de COX-2 foi similar entre os grupos (p = 0,5637) e entre os dias (p = 0,9843). Portanto, o emprego das células tronco mesenquimais xenógenas em enxertos cutâneos promoveu menor ocorrência de necrose, favorecendo sua cicatrização, e não induziu o processo inflamatório, sendo assim factível seu uso em cirurgias reconstrutivas.

The present study aimed to assess inflammation in skin autografts obtained on the third, seventh and fourteenth postoperative day, in addition, it sought to determine differences in the healing process in the group treated with xenogenous mesenchymal stem cells in relation to to the control group using microscopic and immunohistochemical evaluation. Microscopic evaluation was performed using histological sections, stained by the hematoxylin-eosin (HE) histochemistry technique, and immunohistochemistry with sections were subjected to specific antibodies. The variables analyzed were the number of vessels, inflammatory cells (COX-2 and Macrophages) and the presence of necrosis. The data were analyzed statistically by software R. The number of vessels was higher (p< 0.0001) ) in the treatment group (GT) during day 3, while in the control group (CG) it was higher on day 7. On day 3 there was a lower percentage of necrosis in the treatment group (GT) (p = 0.038). On the other evaluated days, there was no difference between the percentage of necrosis observed in the two treatments (p = 0.98), being 53% for the control group (CG) and 47% for the treatment group (GT). Regarding the number of macrophages, there was no difference between groups (p = 0.5637). However, between days there was a significant difference (p = 0.0223), with a lower number of macrophages on the third day. The immunostaining of COX-2 was similar between groups (p = 0.5637) and between days (p = 0.9843). Therefore, the use of xenogenous mesenchymal stem cells in skin grafts promoted a lower occurrence of necrosis, favoring its healing, and did not induce the inflammatory process, thus making its use in reconstructive surgery feasible.

Diminuição do índice de necrose em enxertos cutâneos em coelhos mediante a aplicação de células tronco mesenquimais xenógenas / Reducing of the necrosis index in skin grafts in rabbits through application of xenogenous mesenchymal stem cells

O presente estudo teve como objetivo avaliar a inflamação em auto-enxertos cutâneos obtidos no terceiro, sétimo e décimo quarto dia de pós-operatório, além disso, buscou-se determinar diferenças no processo de cicatrização no grupo tratado com células tronco mesenquimais xenógenas em relação ao grupo controle utilizando a avaliação microscópica e imuno-histoquímico. A avaliação microscópica foi realizada utilizando cortes histológicos corados pela técnica de histoquímica com hematoxilina-eosina (HE), e a imuno-histoquímica, com cortes submetidos a anticorpos específicos. As variáveis analisadas foram quantidade de vasos, células inflamatórias, COX-2, Macrófagos e presença de necrose. Os dados foram analisados estatisticamente pelo software R. A quantidade de vasos foi maior (p<0,0001) no grupo tratamento (GT) durante o dia 3, enquanto no grupo controle (GC) foi maior no dia 7. No dia 3 houve menor porcentagem de necrose no grupo tratamento (GT) (p = 0,038). Nos demais dias avaliados não houve diferença entre a porcentagem de necrose observada nos dois tratamentos (p = 0,98), sendo de 53% para o grupo controle (GC) e 47% para o grupo tratamento (GT). Em relação ao número de macrófagos não houve diferença entre os grupos (p = 0,5637). Entretanto, entre os dias houve diferença significativa (p = 0,0223), sendo menor número de macrófagos no terceiro dia. A imunomarcação de COX-2 foi similar entre os grupos (p = 0,5637) e entre os dias (p = 0,9843). Portanto, o emprego das células tronco mesenquimais xenógenas em enxertos cutâneos promoveu menor ocorrência de necrose, favorecendo sua cicatrização, e não induziu o processo inflamatório, sendo assim factível seu uso em cirurgias reconstrutivas.(AU)

The present study aimed to assess inflammation in skin autografts obtained on the third, seventh and fourteenth postoperative day, in addition, it sought to determine differences in the healing process in the group treated with xenogenous mesenchymal stem cells in relation to to the control group using microscopic and immunohistochemical evaluation. Microscopic evaluation was performed using histological sections, stained by the hematoxylin-eosin (HE) histochemistry technique, and immunohistochemistry with sections were subjected to specific antibodies. The variables analyzed were the number of vessels, inflammatory cells (COX-2 and Macrophages) and the presence of necrosis. The data were analyzed statistically by software R. The number of vessels was higher (p< 0.0001) ) in the treatment group (GT) during day 3, while in the control group (CG) it was higher on day 7. On day 3 there was a lower percentage of necrosis in the treatment group (GT) (p = 0.038). On the other evaluated days, there was no difference between the percentage of necrosis observed in the two treatments (p = 0.98), being 53% for the control group (CG) and 47% for the treatment group (GT). Regarding the number of macrophages, there was no difference between groups (p = 0.5637). However, between days there was a significant difference (p = 0.0223), with a lower number of macrophages on the third day. The immunostaining of COX-2 was similar between groups (p = 0.5637) and between days (p = 0.9843). Therefore, the use of xenogenous mesenchymal stem cells in skin grafts promoted a lower occurrence of necrosis, favoring its healing, and did not induce the inflammatory process, thus making its use in reconstructive surgery feasible.(AU)

Valuation of angiogenesis in bovine xenografts implanted in intracorporal sites of rabbits as models of in-vivo bioreactors / Avaliação da angiogênese em xenoenxertos bovinos implantados em sítios intracorpóreos de coelhos como modelos de biorreatores in vivo

The aim of this study was to evaluate neovascularization of bovine xenografts implanted in intracorporeal sites of rabbits (bioreactors). 30 rabbits were used, divided into 6 groups, according to the evaluation time (7, 15, 30, 45, and 60 days); each animal received xenogenic implants in 3 different intracorporeal sites (A1 - omentum bag; A2 - intermuscular space of quadriceps femoris; A3 - subperiosteal of ilium bone). Histological assessments graded the presence of angiogenesis, the number of inflammatory cells, newly formed bone tissue, and the presence of giant cells. Histological analyses showed intense angiogenesis in all implanted xenografts. Presence of inflammatory infiltrate and giant cells at the A1 implant site and presence of bone neoformation at the A3 implant site were noted. Degeneration of implants and formation of a fibrous capsule were noted. When comparing the interaction of the site with the days of evaluation, statistical analysis showed a significant difference (p≤0.05) in any time of neovascularization analysis. The vascular endothelial growth factor (VEGF) and inflammatory cells of the omentum in its structure, may have contributed to the greater presence of neovessels and inflammatory cells, a fact that may indicate functionality as a possible bone substitute.(AU)

O objetivo deste estudo foi avaliar a neovascularização de xenoenxertos bovinos implantados em sítios intracorpóreos de coelhos (biorreatores). Foram utilizados 30 coelhos, os quais foram divididos em seis grupos, de acordo com o tempo de avaliação (sete, 15, 30, 45 e 60 dias); cada animal recebeu implantes xenogênicos em três diferentes sítios intracorpóreos (A1 - bolsa de omento; A2 - espaço intermuscular do quadríceps femoral; A3 - subperiosteal do osso ílio). Avaliações histológicas classificaram a presença de angiogênese, o número de células inflamatórias, de tecido ósseo neoformado e a presença de células gigantes. As análises histológicas mostraram intensa angiogênese em todos os xenoenxertos implantados. Observou-se presença de infiltrado inflamatório e células gigantes no local do implante A1 e presença de neoformação óssea no local do implante A3. Ao mesmo tempo, a degeneração dos implantes e a formação de uma cápsula fibrosa foram observadas. Ao comparar a interação do local com os dias de avaliação, a análise estatística mostrou diferença significativa (P≤0,05) em qualquer momento da análise de neovascularização. O fator de crescimento endotelial vascular (VEGF) e as células inflamatórias do omento em sua estrutura podem ter contribuído para a maior presença de neovasos e células inflamatórias, fato que pode indicar funcionalidade como possível substituto ósseo.(AU)

A utilização do laser de baixa intensidade na cicatrização de ferida em cão / The use of low intensity laser in wound healing in dog

Background: Low-intensity laser is effective in cellular metabolism, analgesia, and tissue repair. The bioelectric, bioenergetic, and biochemical effects of laser therapy stimulate local circulation, collagen formation, and epithelization. The objective of this study was to report the use of gallium-aluminum arsenide (GaAlAs) laser (830 nm) in healing two woundscaused by necrosis in a dog. Case: An 8-year-old bitch, a rescued victim of animal abuse, had tibiotarsal dislocation in the left posterior limb. Orthopedic surgery was performed with the placement of an external fixation device with six pins in the distal third of the left posterior limb. A radiographic examination performed 42 days after the surgery revealed the loss of the tibiotarsal ratio, decreased radiopacity of the carpal bones, edema, inflammation, muscle atrophy, and the rotation of the anatomical axis of the metatarsals and phalanges. It was then decided to perform a second orthopedic surgery, in which a bone graft and arthrodesis with an 8-screw titanium plate were performed. Four of the plate screws were placed proximally to the tibia and four distally to the tarsus in addition to a screw and a pin transfixed through the distal metaphyseal region of the tibia and calcaneus. Traction was felt during suturing in the dermis and epidermis of the limb, suggesting the possibility of dehiscence of the stitches. After 3 h of surgery, the limb was cold and edematous. After 5 days, the tissue of the medial region of the tarsus developed necrosis, exposing a wound 6 cm long, 1.5 cm wide, and 2 mm deep (wound 1). Another necrotic lesion was observed in the dorsal region of the tarsos - 6.5 cm long, 2 cm wide, 3 mm deep, and exposing 5 cm of the titanium plate (wound 2). Therapy with GaAlAs laser was then performed over the entire length of the wounds. In each therapeutic session, the laser was first used in punctual mode at 10 J/cm², 830 nm, 20 s at each point of the length of the lesion and then in scan mode at 10 J/cm², 830 nm, 1000 Hz, and 40 s continuously. Laser therapy sessions were conducted at 2-4 day intervals, with a 12-day interval between the eighth and ninth sessions. During the entire treatment, cleansing and debridement of the wounds were performed every 48 h with saline and chlorhexidine digluconate, using a compression bandage, as described earlier. Wound 1 healed completely after two laser therapy sessions. In wound 2, tissue repair stagnated after the ninth and last laser session, leaving 4 cm of the titanium plate still exposed. The limb could not support the body weight of the patient, and radiographic examination revealed that the anatomical axis of the metatarsals and the phalanges was rotated and bone conformation was poor. Given the anatomical conditions associated with the patient's clinical picture, it was decided to amputate the limb between the femur and tibia. Discussion: Therapeutic lasers act on mitochondrial respiration, increasing respiratory metabolism and stimulating DNA synthesis and tissue proliferation. In the present case, there was a decrease in inflammatory cells, edema, and the size of the wounds. The pathological conditions of the affected site, influence of trauma, and degree of tissue damage affected the results of the laser therapy. Despite the size difference between wounds 1 and 2, the exposed titanium plate was a determining factor for the partial healing of wound 2.

Use of a morcellized fragment of bone as a bone graft in a femoral fracture repair / Uso de fragmento ósseo morcelizado como enxerto ósseo no reparo de fratura femoral

As one of the most frequent reasons for presentation at the orthopedic services in veterinary practice, long bone fractures need bone continuity for consolidation to take place. This case report has demonstrates the use of a morcellized fragment of bone as a bone graft in a femoral fracture with major bone loss. A mixed-breed adult cat with a segmental femoral fracture with a large longitudinal fissure in the central bone fragment was submitted to an interlocking nail osteosynthesis. During the procedure a fracture occurred along the fissure resulting in two bone fragments with significant bone loss. Fragments were morcellized and applied over the defect to act as a bone graft. By the 15th day after the surgery, the cat had a normal gait and showed no pain response, and bone consolidation occurred after 7 months. Once harvesting of humeral, femoral and tibial bone grafts can be frustrating in cats, resulting in just small amounts of bone, the morcellation of the central fragments was vital to provide sufficient graft to cover the big defect in the femoral shaft. The authors suggest that autologous fresh morcellized cortical bone fragments can be an adjunct to the treatment of comminuted fractures in cats, as an alternative to more traditional repairs of comminuted fracture.(AU)

Fraturas de ossos longos necessitam de continuidade óssea para que a consolidação ocorra. Este relato de caso tem como objetivo demonstrar o uso de um fragmento ósseo morcelizado com a função de enxerto ósseo em uma fratura de fêmur com presença de uma grande falha óssea entre os fragmentos. Um gato adulto, sem raça definida, com uma fratura múltipla em fêmur com presença de uma fissura longitudinal no fragmento central foi submetido à osteossíntese com uso de haste bloqueada. Durante o processo, ocorreu uma fragmentação a partir da fissura, o que resultou na presença de dois fragmentos ósseos com uma grande porção de perda óssea entre os dois. Os fragmentos ósseos restantes do fragmento central foram morcelizados e aplicados no defeito para atuar com enxerto ósseo. Quinze dias após a cirurgia o paciente apresentou apoio normal e ausência de dor, e consolidação óssea ocorreu em 7 meses pós operatórios. Uma vez que a coleta de enxerto nos gatos resulta em pouca quantidade de osso, a morcelização do fragmento central foi vital para promover enxerto suficiente para cobrir o defeito ósseo. Os autores sugerem que o uso de enxerto cortical autólogo fresco morcelizado pode ser um adjuvante no tratamento de fraturas cominutivas em gatos, como um tratamento alternativo à terapia convencional.(AU)

Use of a morcellized fragment of bone as a bone graft in a femoral fracture repair / Uso de fragmento ósseo morcelizado como enxerto ósseo no reparo de fratura femoral

As one of the most frequent reasons for presentation at the orthopedic services in veterinary practice, long bone fractures need bone continuity for consolidation to take place. This case report has demonstrates the use of a morcellized fragment of bone as a bone graft in a femoral fracture with major bone loss. A mixed-breed adult cat with a segmental femoral fracture with a large longitudinal fissure in the central bone fragment was submitted to an interlocking nail osteosynthesis. During the procedure a fracture occurred along the fissure resulting in two bone fragments with significant bone loss. Fragments were morcellized and applied over the defect to act as a bone graft. By the 15th day after the surgery, the cat had a normal gait and showed no pain response, and bone consolidation occurred after 7 months. Once harvesting of humeral, femoral and tibial bone grafts can be frustrating in cats, resulting in just small amounts of bone, the morcellation of the central fragments was vital to provide sufficient graft to cover the big defect in the femoral shaft. The authors suggest that autologous fresh morcellized cortical bone fragments can be an adjunct to the treatment of comminuted fractures in cats, as an alternative to more traditional repairs of comminuted fracture.

Fraturas de ossos longos necessitam de continuidade óssea para que a consolidação ocorra. Este relato de caso tem como objetivo demonstrar o uso de um fragmento ósseo morcelizado com a função de enxerto ósseo em uma fratura de fêmur com presença de uma grande falha óssea entre os fragmentos. Um gato adulto, sem raça definida, com uma fratura múltipla em fêmur com presença de uma fissura longitudinal no fragmento central foi submetido à osteossíntese com uso de haste bloqueada. Durante o processo, ocorreu uma fragmentação a partir da fissura, o que resultou na presença de dois fragmentos ósseos com uma grande porção de perda óssea entre os dois. Os fragmentos ósseos restantes do fragmento central foram morcelizados e aplicados no defeito para atuar com enxerto ósseo. Quinze dias após a cirurgia o paciente apresentou apoio normal e ausência de dor, e consolidação óssea ocorreu em 7 meses pós operatórios. Uma vez que a coleta de enxerto nos gatos resulta em pouca quantidade de osso, a morcelização do fragmento central foi vital para promover enxerto suficiente para cobrir o defeito ósseo. Os autores sugerem que o uso de enxerto cortical autólogo fresco morcelizado pode ser um adjuvante no tratamento de fraturas cominutivas em gatos, como um tratamento alternativo à terapia convencional.

Use of a morcellized fragment of bone as a bone graft in a femoral fracture repair / Uso de fragmento ósseo morcelizado como enxerto ósseo no reparo de fratura femoral

As one of the most frequent reasons for presentation at the orthopedic services in veterinary practice, long bone fractures need bone continuity for consolidation to take place. This case report has demonstrates the use of a morcellized fragment of bone as a bone graft in a femoral fracture with major bone loss. A mixed-breed adult cat with a segmental femoral fracture with a large longitudinal fissure in the central bone fragment was submitted to an interlocking nail osteosynthesis. During the procedure a fracture occurred along the fissure resulting in two bone fragments with significant bone loss. Fragments were morcellized and applied over the defect to act as a bone graft. By the 15th day after the surgery, the cat had a normal gait and showed no pain response, and bone consolidation occurred after 7 months. Once harvesting of humeral, femoral and tibial bone grafts can be frustrating in cats, resulting in just small amounts of bone, the morcellation of the central fragments was vital to provide sufficient graft to cover the big defect in the femoral shaft. The authors suggest that autologous fresh morcellized cortical bone fragments can be an adjunct to the treatment of comminuted fractures in cats, as an alternative to more traditional repairs of comminuted fracture.

Fraturas de ossos longos necessitam de continuidade óssea para que a consolidação ocorra. Este relato de caso tem como objetivo demonstrar o uso de um fragmento ósseo morcelizado com a função de enxerto ósseo em uma fratura de fêmur com presença de uma grande falha óssea entre os fragmentos. Um gato adulto, sem raça definida, com uma fratura múltipla em fêmur com presença de uma fissura longitudinal no fragmento central foi submetido à osteossíntese com uso de haste bloqueada. Durante o processo, ocorreu uma fragmentação a partir da fissura, o que resultou na presença de dois fragmentos ósseos com uma grande porção de perda óssea entre os dois. Os fragmentos ósseos restantes do fragmento central foram morcelizados e aplicados no defeito para atuar com enxerto ósseo. Quinze dias após a cirurgia o paciente apresentou apoio normal e ausência de dor, e consolidação óssea ocorreu em 7 meses pós operatórios. Uma vez que a coleta de enxerto nos gatos resulta em pouca quantidade de osso, a morcelização do fragmento central foi vital para promover enxerto suficiente para cobrir o defeito ósseo. Os autores sugerem que o uso de enxerto cortical autólogo fresco morcelizado pode ser um adjuvante no tratamento de fraturas cominutivas em gatos, como um tratamento alternativo à terapia convencional.

Caprine demineralized bone matrix (DBMc) in the repair of non-critical bone defects in rabbit tibias. A new bone xenograft

Purpose To evaluate the use of demineralized bone matrix of caprine origin in experimental bone defects of the tibia in New Zealand rabbits. Methods Fragments of the tibia diaphysis were collected aseptically from clinically healthy goats. The bones were sectioned into 1 cm fragments and stored at -20°C for subsequent hydrochloric acid (HCL) demineralization. A 70 mg portion of DBMc was used to fill the experimental bone defects. Twenty-four female adult New Zealand rabbits were divided into 2 groups: the MG (matrix group, left tibia) and CG (control group, right tibia). Additionally, they were separated into 4 groups with 6 animals, according to the period of analysis (15, 30, 60 and 90 days postoperatively). Using microCT, volumetric parameters were evaluated: bone volume, relationship between bone volume and total volume, bone surface area, relationship between bone surface area and total volume, number of trabeculae, trabecular thickness and trabecular separation. Results There was a statistically significant difference (P 0.05) between groups considering bone volume (BV) and bone:total volume (BV/TV), on 15, 30 and 90 days postoperatively. Control group showed a statistically significant superiority (P < 0.05) considering the mean of the variables bone surface (BS), number of trabeculae (Tb.N) and between bone surface and total volume (BS/TV) at 15 and 90 days. Conclusions Caprine demineralized bone matrix was safe and tolerable. No signs of material rejection were seen macroscopically. It is an alternative for the treatment of bone defects when autologous graft is not available or in insufficient quantities.(AU)

Aloenxertos ósseos e enxerto sintético de hidroxiapatita em falha óssea ulnar em galinhas (Gallus gallus domesticus), aspectos radiográficos e histológicos / Bone allografts and synthetic grafts hydroxyapatite on ulnar bone defect in fowl (Gallus gallus domesticus), radiographic and histological aspects

Dos atendimentos ortopédicos realizados em aves no HCV-UFRGS, 86% são fraturas, sendo aproximadamente 30% delas cominutivas com perda óssea expressiva, justificando a importância da utilização de enxertos em fraturas de aves. O objetivo deste trabalho foi avaliar dois aloenxertos e enxerto sintético de hidroxiapatita em defeito ósseo de galinhas. Utilizaram-se 30 galinhas separadas em três grupos: aloenxerto congelado em ultra-freezer (GUF), aloenxerto congelado em nitrogênio líquido (GNL) e enxerto sintético de hidroxiapatita deficiente em cálcio (GHA). Nos três grupos, os enxertos foram aplicados com placas e parafusos bloqueados de 2mm na ulna direita das aves, avaliando-se a evolução por meio de exames radiográficos até serem completados 90 dias de pós-operatório e o resultado final mediante exame histológico. A média e desvio-padrão relacionando o tempo de consolidação óssea radiográfica foi: GNL 61,67±21,79 dias (90% de consolidação), GUF 47,14±13,50 dias (70% de consolidação) e GHA 70±18,17 dias (60% de consolidação). Houve diferença significativa no tempo de consolidação óssea entre o GUF e o GHA. Histologicamente, os enxertos do GUF foram os que estavam em consolidação mais avançada. Os aloenxertos do GNL foram superiores no preenchimento de falha óssea ulnar de galinhas.(AU)

Of the orthopedic visits performed on birds at HCV-UFRGS, 86% are fractures, and approximately 30% of them are comminuted with expressive bone loss, justifying the importance of the use of grafts in bird fractures. The objective of this work was to test two allografts and a synthetic HADC graft on finishing in Gallus gallus domesticus. 30 laying hens were used, divided in three groups: frozen allograft in ultrafreezer (UFG); frozen allograft in liquid nitrogen (LNG); calcium deficient synthetic hydroxyapatite graft (HAG). The three graft groups were exposed to serial radiographs until the 90 postoperative days, as well as the histological examination at the end of the experiment were: LNG 61.67±21.79 days (90% consolidation), UFG 47.14±13.50 days (70% consolidation) and HAG 70±18.17 days (60% consolidation). There was a significant difference in bone healing time between GUF and GHA. Histologically, GUF grafts were the ones that were in the most advanced consolidation. LNG allografts were superior in filling ulnar bone failure of fowl.(AU)

Aloenxertos ósseos e enxerto sintético de hidroxiapatita em falha óssea ulnar em galinhas (Gallus gallus domesticus), aspectos radiográficos e histológicos / Bone allografts and synthetic grafts hydroxyapatite on ulnar bone defect in fowl (Gallus gallus domesticus), radiographic and histological aspects

Dos atendimentos ortopédicos realizados em aves no HCV-UFRGS, 86% são fraturas, sendo aproximadamente 30% delas cominutivas com perda óssea expressiva, justificando a importância da utilização de enxertos em fraturas de aves. O objetivo deste trabalho foi avaliar dois aloenxertos e enxerto sintético de hidroxiapatita em defeito ósseo de galinhas. Utilizaram-se 30 galinhas separadas em três grupos: aloenxerto congelado em ultra-freezer (GUF), aloenxerto congelado em nitrogênio líquido (GNL) e enxerto sintético de hidroxiapatita deficiente em cálcio (GHA). Nos três grupos, os enxertos foram aplicados com placas e parafusos bloqueados de 2mm na ulna direita das aves, avaliando-se a evolução por meio de exames radiográficos até serem completados 90 dias de pós-operatório e o resultado final mediante exame histológico. A média e desvio-padrão relacionando o tempo de consolidação óssea radiográfica foi: GNL 61,67±21,79 dias (90% de consolidação), GUF 47,14±13,50 dias (70% de consolidação) e GHA 70±18,17 dias (60% de consolidação). Houve diferença significativa no tempo de consolidação óssea entre o GUF e o GHA. Histologicamente, os enxertos do GUF foram os que estavam em consolidação mais avançada. Os aloenxertos do GNL foram superiores no preenchimento de falha óssea ulnar de galinhas.(AU)

Of the orthopedic visits performed on birds at HCV-UFRGS, 86% are fractures, and approximately 30% of them are comminuted with expressive bone loss, justifying the importance of the use of grafts in bird fractures. The objective of this work was to test two allografts and a synthetic HADC graft on finishing in Gallus gallus domesticus. 30 laying hens were used, divided in three groups: frozen allograft in ultrafreezer (UFG); frozen allograft in liquid nitrogen (LNG); calcium deficient synthetic hydroxyapatite graft (HAG). The three graft groups were exposed to serial radiographs until the 90 postoperative days, as well as the histological examination at the end of the experiment were: LNG 61.67±21.79 days (90% consolidation), UFG 47.14±13.50 days (70% consolidation) and HAG 70±18.17 days (60% consolidation). There was a significant difference in bone healing time between GUF and GHA. Histologically, GUF grafts were the ones that were in the most advanced consolidation. LNG allografts were superior in filling ulnar bone failure of fowl.(AU)

Mechanical properties of the sciatic nerve following combined transplantation of analytically extracted acellular allogeneic nerve and adipose-derived mesenchymal stem cells

Purpose To investigate the effects of Chemically Extracted Acellular Nerves (CEANs) when combined with Adipose-Derived mesenchymal Stem Cell (ADSC) transplantation on the repair of sciatic nerve defects in rabbits. Methods A total of 71 six-month-old Japanese rabbit were used in this study. Twenty rabbits served as sciatic nerve donors, while the other 51 rabbits were randomly divided into Autologous Nerve Transplantation Group (ANT, n=17), CEAN group (n=17) and CEAN-ADSCs group (n=17). In all these groups, the rabbits left sciatic nerves were injured before the experiment, and the uninjured sciatic nerves on their right side were used as the control (CON). Electrophysiological tests were carried out and sciatic nerves were prepared for histomorphology and stretch testing at 24 weeks post-transplant. Results There were significant differences between ANT and Con groups in amplitude (AMP): P=0.031; motor nerve conduction velocity (MNCV): P=0.029; Maximum stress: P=0.029; and Maximum strain P=0.027. There were also differences between the CEAN and CEAN+ADSCs groups in AMP: P=0.026, MNCV: P=0.024; Maximum stress: P=0.025 and Maximum strain: P=0.030. No significant differences in these parameters were observed when comparing the ANT and CEAN+SACN groups (MNCV: P=0.071) or the CEAN and ANT groups (Maximum stress: P=0.069; Maximum strain P=0.077). Conclusion Addition of ADSCs has a significant impact on the recovery of nerve function, morphology, and tensile mechanical properties following sciatic nerve injury.(AU)

Effects of canine adipose-derived mesenchymal stem cells on the epithelialization of rabbits' skin autograft (Oryctolagus cuniculus) / Efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães na epitelização de autoenxertos de pele em coelhos (Oryctolagus cuniculus)

The present study aimed to evaluate the effects of mesenchymal stem cells derived from canine adipose tissue in the healing process of full-thickness mesh skin grafts in rabbits. The stem cells were collected from young dogs; and, after characterization, remained in cryopreservation, in independent doses containing 2 x 106 cells. The mesh distal limb graft technique was performed in 60 rabbits, divided into three groups, CG (Control Group), GT1 (Intralesional Stem Cell Treated Group), and GT2 (Intravenous Stem Cell Treated Group), containing 20 animals each. After grafting, each group was randomly divided into four subgroups according to euthanasia time 3, 7, 14, and 30 days, containing five animals in each group. Animals of GT1_14, GT1_30, and GT2_14, GT2_30 subgroups received a second dose of xenogeneic cells on the seventh day. Meanwhile, animals from GT1_30 and GT2_30 received the third dose of xenogeneic cells on day 14. The groups treated with xenogeneic stem cells positively affected type III collagen re-epithelialization and deposition, and possibly GT1 had a controlled inflammatory response. However, no effect on angiogenesis. Thus, it was possible to demonstrate tolerance and therapeutic action of mesenchymal stem cells from canine adipose tissue in skin grafts in rabbits.(AU)

O presente estudo teve como principal objetivo avaliar os efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães no processo de cicatrização de autoenxertos de pele de espessura total em malha em coelhos. As células-tronco foram coletadas de cães jovens, após a caracterização estas permaneceram em criopreservação, em doses individuais contendo 2 x 106 células. A técnica de enxerto em malha na região distal do membro foi realizada em 60 coelhos, divididos em três grupos, GC (Grupo Controle), GT1 (Grupo tratado com células-tronco intralesional) e GT2 (Grupo tratado com células-tronco via endovenosa), contendo 20 animais cada. Imediatamente após a enxertia, cada grupo foi dividido aleatoriamente em quatro subgrupos, de acordo com o tempo de eutanásia 3, 7, 14 e 30 dias contendo cinco animais cada. Animais dos subgrupos GT1_14, GT1_30 e GT2_14, GT2_30 receberam uma segunda dose de células xenógenas no sétimo dia. Ademais, animais do GT1_30 e do GT2_30 receberam a terceira dose de células xenógenas no dia 14. Os grupos tratados com células-tronco xenógenas tiveram um efeito positivo na reepitelização e deposição de colágeno tipo III, e possivelmente, o GT1 teve uma resposta inflamatória controlada, entretanto o efeito na angiogênese não foi observado. Dessa forma, foi possível demonstrar que houve tolerância e ação terapêutica das células-tronco mesenquimais derivadas do tecido adiposo de cães em enxertos de pele em coelhos.(AU)

Effects of canine adipose-derived mesenchymal stem cells on the epithelialization of rabbits' skin autograft (Oryctolagus cuniculus) / Efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães na epitelização de autoenxertos de pele em coelhos (Oryctolagus cuniculus)

The present study aimed to evaluate the effects of mesenchymal stem cells derived from canine adipose tissue in the healing process of full-thickness mesh skin grafts in rabbits. The stem cells were collected from young dogs; and, after characterization, remained in cryopreservation, in independent doses containing 2 x 106 cells. The mesh distal limb graft technique was performed in 60 rabbits, divided into three groups, CG (Control Group), GT1 (Intralesional Stem Cell Treated Group), and GT2 (Intravenous Stem Cell Treated Group), containing 20 animals each. After grafting, each group was randomly divided into four subgroups according to euthanasia time 3, 7, 14, and 30 days, containing five animals in each group. Animals of GT1_14, GT1_30, and GT2_14, GT2_30 subgroups received a second dose of xenogeneic cells on the seventh day. Meanwhile, animals from GT1_30 and GT2_30 received the third dose of xenogeneic cells on day 14. The groups treated with xenogeneic stem cells positively affected type III collagen re-epithelialization and deposition, and possibly GT1 had a controlled inflammatory response. However, no effect on angiogenesis. Thus, it was possible to demonstrate tolerance and therapeutic action of mesenchymal stem cells from canine adipose tissue in skin grafts in rabbits.(AU)

O presente estudo teve como principal objetivo avaliar os efeitos das células-tronco mesenquimais derivadas do tecido adiposo de cães no processo de cicatrização de autoenxertos de pele de espessura total em malha em coelhos. As células-tronco foram coletadas de cães jovens, após a caracterização estas permaneceram em criopreservação, em doses individuais contendo 2 x 106 células. A técnica de enxerto em malha na região distal do membro foi realizada em 60 coelhos, divididos em três grupos, GC (Grupo Controle), GT1 (Grupo tratado com células-tronco intralesional) e GT2 (Grupo tratado com células-tronco via endovenosa), contendo 20 animais cada. Imediatamente após a enxertia, cada grupo foi dividido aleatoriamente em quatro subgrupos, de acordo com o tempo de eutanásia 3, 7, 14 e 30 dias contendo cinco animais cada. Animais dos subgrupos GT1_14, GT1_30 e GT2_14, GT2_30 receberam uma segunda dose de células xenógenas no sétimo dia. Ademais, animais do GT1_30 e do GT2_30 receberam a terceira dose de células xenógenas no dia 14. Os grupos tratados com células-tronco xenógenas tiveram um efeito positivo na reepitelização e deposição de colágeno tipo III, e possivelmente, o GT1 teve uma resposta inflamatória controlada, entretanto o efeito na angiogênese não foi observado. Dessa forma, foi possível demonstrar que houve tolerância e ação terapêutica das células-tronco mesenquimais derivadas do tecido adiposo de cães em enxertos de pele em coelhos.(AU)

Reconstruction of parietal bone defects with adiposederived mesenchymal stem cells: experimental study

Purpose: This study assessed the regeneration potential of mesenchymal stem cells (MSC) from adipose tissue associated with platelet-rich plasma (PRP) in bone regeneration. Methods: Thirty Wistar rats (Rattus norvegicus albinos) were divided into five groups (according to the grafting material and time to euthanasia): (1) autograft - 14 days (control), (2) autograft - 28 days (control), (3) MSC + PRP - 14 days, (4) MSC + PRP + papaverine - 14 days and (5) MSC + PRP + papaverine - 28 days. After euthanasia, the graft was removed and histological slides were prepared. They were assessed by a blinded pathologist using a previously published histological scale as parameter. Results: There was some degree of neoformed bone trabeculae (NBT) in 93.3% of the samples, as well as osteoblastic activity (OA). The autograft groups (14 and 28 days) had higher levels in the formation of bone trabeculae. Nonparametric data were analyzed using the Wilcoxon-Mann-Whitney test and proved not to be statistically significant at p 0.05. Conclusions: Experimental parietal bone reconstruction, combining MSC, PRP and papaverine presented regeneration in all groups with no significant difference among them.(AU)

Reconstrução cirúrgica da tíbia em fratura mal consolidada em um cão / Surgical reconstruction of tibia in poorly consolidated fracture in a dog

Objetiva-se com este trabalho relatar um caso de reconstrução cirúrgica tibial em uma fratura mal consolidada em um canino, salientando a versatilidade do fixador esquelético externo (FEE) e a importância do enxerto esponjoso como coadjuvante da cicatrização. Para a reconstrução cirúrgica da tíbia, esta foi refraturada, e em seguida, alinhada com o auxílio de pino intramedular de Steinmann temporário. Empregou-se fixação esquelética externa associada à enxertia óssea esponjosa autógena coletada da asa do ílio. No protocolo pós-cirúrgico, foi recomendado os mesmos cuidados e medicações de uma osteossíntese habitual. Decorridos 35 dias da cirurgia, observou-se perda da linha de fratura e formação de calo ósseo, permitindo a remoção do FEE. O animal voltou a apoiar o membro normalmente, apenas com um leve encurtamento do mesmo, mas sem prejuízo à deambulação.

The aim of this study is to report a case of tibial surgical reconstruction in a poorly consolidated canine fracture, emphasizing the versatility of the external skeletal fixator (ESF) and the importance of the cancellous graft as an adjunct to healing. For surgical reconstruction of the tibia, it was refracted and then aligned with support by temporary Steinmann intramedullary pin. External skeletal fixation was applied in association with bone grafting of spongy autogenous tissue collected by iliac wing. In the post-surgical protocol, the same care and medications as usual for osteosynthesis were recommended. Fracture line loss and bone callus formation were observed thirty-five days after the surgery, allowing the removal of the ESF. The animal returned to support the limb normally, only with a slight shortening of the limb, but without prejudice to the walking.

Reconstrução cirúrgica da tíbia em fratura mal consolidada em um cão / Surgical reconstruction of tibia in poorly consolidated fracture in a dog

Objetiva-se com este trabalho relatar um caso de reconstrução cirúrgica tibial em uma fratura mal consolidada em um canino, salientando a versatilidade do fixador esquelético externo (FEE) e a importância do enxerto esponjoso como coadjuvante da cicatrização. Para a reconstrução cirúrgica da tíbia, esta foi refraturada, e em seguida, alinhada com o auxílio de pino intramedular de Steinmann temporário. Empregou-se fixação esquelética externa associada à enxertia óssea esponjosa autógena coletada da asa do ílio. No protocolo pós-cirúrgico, foi recomendado os mesmos cuidados e medicações de uma osteossíntese habitual. Decorridos 35 dias da cirurgia, observou-se perda da linha de fratura e formação de calo ósseo, permitindo a remoção do FEE. O animal voltou a apoiar o membro normalmente, apenas com um leve encurtamento do mesmo, mas sem prejuízo à deambulação.(AU)

The aim of this study is to report a case of tibial surgical reconstruction in a poorly consolidated canine fracture, emphasizing the versatility of the external skeletal fixator (ESF) and the importance of the cancellous graft as an adjunct to healing. For surgical reconstruction of the tibia, it was refracted and then aligned with support by temporary Steinmann intramedullary pin. External skeletal fixation was applied in association with bone grafting of spongy autogenous tissue collected by iliac wing. In the post-surgical protocol, the same care and medications as usual for osteosynthesis were recommended. Fracture line loss and bone callus formation were observed thirty-five days after the surgery, allowing the removal of the ESF. The animal returned to support the limb normally, only with a slight shortening of the limb, but without prejudice to the walking.(AU)

Development of a lumbosacral intervertebral cage prototype for dogs

ABSTRACT: Several surgical procedures aim to decompress and/or stabilize the lumbosacral (LS) joint of dogs; however, the lumbar interbody fusion technique, by using a cage combined with a bone graft, is the most indicated and used in human medicine. No specific implant is available for application to the canine lumbosacral joint. Thus, this study measured lumbosacral discs in large dogs, determined whether a human cage model could fit the dogs L7-S1 intervertebral space, and developed a LS cage prototype for dogs. Ten cadaveric lumbosacral spines from adult dog weighing 20-35kg were used. The dogs had died for reasons unrelated to this study. The vertebral body dimensions and the L7-S1 intervertebral space occupied by the intervertebral disc were measured by lateral and ventrodorsal radiographs and by computed tomography in the dorsal, sagittal, and transverse views. Measurements were also taken of the anatomical specimens in the sagittal and transverse planes. After measuring the intervertebral discs, the following mean measures were obtained for L7-S1 discs: height 12.23mm, dorsal thickness 3.3mm, central thickness 4mm, ventral thickness 5.5mm, and width 24.74mm. The human lumbar cage models from brands LDR, Baumer Orthopedics, Stryker, Synthes, and Vertebral Technologies, Inc. and cervical stabilization cages from the brands B-Braun and Stryker were evaluated and were found to be unsuitable for large dogs. Cervical human cages had measurements similar to those found in this study; however, due to their quadrangular shape, the possibility of being introduced surgically through the surgical accesses available for the articulation between L7-S1 in dogs without injuring the cauda equina or the L7 root is small. A cage model was then developed using 3D modelling software. It was designed for insertion via dorsal laminectomy in the lateral portions of the intervertebral space. To avoid cauda equina lesion, the implant model was developed to be placed laterally to the midline. The cage surface is serrated to prevent using the locking screw to fix it, thus avoiding further injury to nerve structures. The serrated surfaces are also designed to avoid cage migration and promote stability. The prototype allows graft placement in the surrounding intervertebral space, which is fundamental for fusion through integration between the cage and the endplates as well as for bone growth between and around the cage. It was also considered studies on humans showing that the lateral regions of the endplates support a more considerable load. Biomechanical and in vivo studies on the developed model are necessary to evaluate the actual degree of distraction, mobility and the long-term rate of fusion between L7 and S1 and its possible impact on the adjacent motor units, combined or not with dorsal fixation techniques.

RESUMO: Vários procedimentos cirúrgicos visam descomprimir e/ou estabilizar a articulação lombossacra (LS) de cães; no entanto, a técnica de fusão lombar, usando um cage intersomático combinado com um enxerto ósseo, é a mais indicada e utilizada na medicina humana. Não há implante específico disponível para aplicação na articulação lombossacra canina. Assim, neste estudo foi realizada a mensuração do espaço do disco intervertebral lombossacro de cães de raças grandes, para verificar se algum modelo de cage usado na medicina humana poderia ser usado no espaço intervertebral L7-S1 de cães. O segundo objetivo foi desenvolver um protótipo de cage lombossacro para cães. Foram utilizadas dez colunas lombossacras provenientes de cadáveres de cães adultos com peso entre 20 e 35kg. Os cães vieram a óbito por razões não relacionadas a este estudo. As dimensões do corpo vertebral e o espaço intervertebral L7-S1 ocupado pelo disco intervertebral foram medidos por radiografias laterais e ventrodorsais e por tomografia computadorizada nos cortes dorsal, sagital e transversal. Também foram realizadas mensurações das peças anatômicas nos planos sagital e transversal. Após a mensuração dos discos intervertebrais, foram obtidas as seguintes medidas médias dos discos L7-S1: altura 12,23mm, espessura dorsal 3,3mm, espessura central 4mm, espessura ventral 5,5mm e largura 24,74mm. Os modelos de cage lombar humano das marcas LDR, Baumer Orthopaedics, Stryker, Synthes e Vertebral Technologies, Inc. não possuíam dimensões adequadas para os cães. Cages de estabilização cervical das marcas B-Braun e Stryker também foram avaliados e apresentaram medidas semelhantes às encontradas neste estudo; no entanto, devido à sua forma quadrangular, a possibilidade de serem introduzidos cirurgicamente através das abordagens disponíveis para a articulação entre L7-S1 em cães sem lesionar a cauda equina ou a raiz L7 é pequena. Um modelo de cage foi então desenvolvido usando-se o software de modelagem 3D. Foi projetado para inserção via laminectomia dorsal nas porções laterais do espaço intervertebral. Para evitar a lesão da cauda equina, o modelo de implante foi desenvolvido para ser colocado lateralmente à linha média. A superfície do cage é serrilhada para evitar o uso do parafuso de travamento, evitando-se lesões adicionais às estruturas nervosas. As superfícies serrilhadas também foram projetadas para evitar a migração do cage e promover estabilidade. O protótipo permite a colocação do enxerto no espaço intervertebral circundante, fundamental para a fusão através da integração entre o cage e as placas vertebrais terminais, bem como para o crescimento ósseo entre e ao redor do implante. Também foram considerados estudos em seres humanos que mostraram que as regiões laterais das placas vertebrais terminais suportam uma carga maior. São necessários estudos biomecânicos e in vivo do modelo desenvolvido para avaliar o grau real de distração, mobilidade e a taxa de fusão a longo prazo entre L7 e S1 e seu possível impacto nas unidades motoras adjacentes, quando combinado ou não com técnicas de fixação dorsal.

Application of a meshed skin graft in the surgical bed immediately after resection of neurofibrosarcoma in the distal limb region of a dog

Background: Malignant peripheral nerve sheath tumors are neurogenic neoplasms that originate from cells that surroundthe axons of peripheral nerves. Surgery is the treatment of choice for peripheral nerve sheath tumors. They have a betterprognosis when the lesion is in the extremity of a limb and the surgeon leaves wide peripheral margins after resection.However, this procedure makes local treatment a challenge due to difficult wound healing in this region. This report describes a successful case involving the use of a meshed skin graft immediately after resection of a neurofibrosarcoma inthe distal region of the radius bone of a dog.Case: A 6-year-old Boxer bitch weighing 40 kg was admitted with a history of a round, firm, non-ulcerated skin noduleattached to the lateral side of the distal region of the right radius bone, which had been present for about 40 days. Fineneedle aspiration cytology of the lesion showed the presence of mesenchymal cells, suggesting a sarcoma. Thus, the decision was made for an incisional biopsy to confirm the diagnosis and for the preparation of a subdermal pattern tubular flapfor subsequent rotation and transposition to close the wound that would be formed after the complete removal of the lesion.After the 7th postoperative day, the diagnosis of low-grade neurofibrosarcoma was confirmed and due to the presence ofnecrotic onset in the middle portion of the tubular flap, further surgical intervention was scheduled for the resection of thetube flap, en bloc removal of the neoplastic lesion with peripheral margins of 2 cm, and wound closure with a free skingraft. A mesh skin graft was made with a portion of the right flank skin. The mesh graft was carefully implanted on therecipient bed using simple interrupted sutures with a 3-0 non-absorbable monofilament suture material. A dressing madewith water-based sterile lubricating solution and...

Application of a meshed skin graft in the surgical bed immediately after resection of neurofibrosarcoma in the distal limb region of a dog

Background: Malignant peripheral nerve sheath tumors are neurogenic neoplasms that originate from cells that surroundthe axons of peripheral nerves. Surgery is the treatment of choice for peripheral nerve sheath tumors. They have a betterprognosis when the lesion is in the extremity of a limb and the surgeon leaves wide peripheral margins after resection.However, this procedure makes local treatment a challenge due to difficult wound healing in this region. This report describes a successful case involving the use of a meshed skin graft immediately after resection of a neurofibrosarcoma inthe distal region of the radius bone of a dog.Case: A 6-year-old Boxer bitch weighing 40 kg was admitted with a history of a round, firm, non-ulcerated skin noduleattached to the lateral side of the distal region of the right radius bone, which had been present for about 40 days. Fineneedle aspiration cytology of the lesion showed the presence of mesenchymal cells, suggesting a sarcoma. Thus, the decision was made for an incisional biopsy to confirm the diagnosis and for the preparation of a subdermal pattern tubular flapfor subsequent rotation and transposition to close the wound that would be formed after the complete removal of the lesion.After the 7th postoperative day, the diagnosis of low-grade neurofibrosarcoma was confirmed and due to the presence ofnecrotic onset in the middle portion of the tubular flap, further surgical intervention was scheduled for the resection of thetube flap, en bloc removal of the neoplastic lesion with peripheral margins of 2 cm, and wound closure with a free skingraft. A mesh skin graft was made with a portion of the right flank skin. The mesh graft was carefully implanted on therecipient bed using simple interrupted sutures with a 3-0 non-absorbable monofilament suture material. A dressing madewith water-based sterile lubricating solution and...(AU)

Transposição de coxim digital associada à órtese articulada caseira como alternativa à amputação de membro pélvico em cão - relato de caso

Os coxins podem ser definidos como a porção mais resistente da pele de cães e gatos, e possuem as funções de sustentação do peso do animal, e a proteção contra as forças de tração e de atrito. As cirurgias que objetivam a reconstrução dos coxins são alternativas viáveis à amputação do membro em diversas situações clínicas. Dentre as opções cirúrgicas, destaca-se a transposição dos coxins. Entretanto, quando se faz necessária a amputação dos dígitos, o encurtamento do membro pode comprometer a deambulação. Uma alternativa neste sentido é a associação à órteses. O objetivo do presente trabalho foi descrever o caso de um cão da raça pitbull, fêmea, com quatro anos de idade e histórico de gangrena úmida da extremidade do membro pélvico esquerdo, submetida à amputação dos dígitos e transposição dos coxins. Durante o período pós-operatório foi desenvolvida uma órtese articulada caseira a fim de facilitar a sustentação do peso e auxiliar na deambulação do animal. A paciente se adaptou ao dispositivo ortopédico e foi acompanhado até a completa reepitelização do membro residual aos 30 dias de pós-operatório. Desta forma, conclui-se que a transposição dos coxins associada à órtese articulada pode ser uma opção viável à amputação do membro pélvico em cães de grande porte.(AU)

The digital pad can be defined as the most resistant area of the skin of the dogs and cats, which functions includes animal weight support and protection against to tractive and frictional forces. The reconstructive surgeries of the digital pad are viable alternatives to the limb amputation in many clinical situations. Among the surgical options, the transposition of the digital pad is highlighted. However, when amputation of the digits is necessary, shortening of the limb can compromise ambulation. An alternative to this, it is the use of orthoses. The aim of this report was to describe the case of a four-years-old female pit bull with clinical history of wet gangrene of left pelvic limb, submitted to transposition of digital pad, obtained from the contralateral hindlimb. An articulate orthosis was projected at postoperative period in order to facilitate weight support and assist the patient ambulation. The patient has adapted itself to the new orthopedic device, and was constantly monitored until complete reepithelialization of the residual limb at 30 days of postoperative. Thus, it can be concluded that the transposition of digital pad associated to the articulate orthosis can be a viable option to the limb amputation in large breed dogs.(AU)